Clutches are employed in many types of vehicles to provide an interruptable transfer of power from a driving force, such as an engine, to a driven mechanism, such as wheels or tracks. Mechanical clutches having clutch plates and friction pads are available in a variety of designs for providing such an interruptable connection between a power source and a driven mechanism. When engaged, the clutch plates and friction pads are forced together so that the clutch elements rotate in unison, thereby causing the power source to drive the driven mechanism. When released, the friction pads, which may be connected to the driven member, are removed from engagement with the clutch plates which generally remain rotating at the speed of the power source.
In many clutch systems a phenomenon termed "flutter" is frequently encountered in which the clutch plates themselves tend to vibrate or move axially about a common clutch shaft. The flutter experienced in such clutch systems is often excessive enough that the clutch plates themselves disintegrate during rotation and damage the entire clutch assembly. In other less excessive cases, clutch plate flutter causes momentary engagement with the friction pads, whereupon such pads become worn and sufficient heat can be generated within the clutch system to present reliability problems.
The problem of clutch plate flutter has been recognized and corresponding solutions have been attempted. For example, disclosed in U.S. Pat. 3,735,474 is the use of an elastomeric element for maintaining a separation between clutch disks. However, such an elastomeric element tends to degrade over time, often due to both the high temperatures experienced within a clutch assembly, and the hydraulic fluid utilized to cool the clutch parts. In addition, special precautions and procedures are required to install the elastomeric spacers within the clutch plates, thus requiring additional labor which adds cost to the clutch assembly.
From the foregoing, it can be seen that a need exists for an improved technique and apparatus which reduces clutch flutter, which operates efficiently and which is easily installed on existing clutch plates.